mac: Only show the access Address Book prompt a fixed number of times.

components/autofill/core/common/autofill_pref_names.h

Index: components/autofill/core/common/autofill_pref_names.h
diff --git a/components/autofill/core/common/autofill_pref_names.h b/components/autofill/core/common/autofill_pref_names.h
index fb580a6565fb888f463160b72d2bc6529fd9bec6..ea830cce1561173c61d4e82bcf7c6d40705f42da 100644
--- a/components/autofill/core/common/autofill_pref_names.h
+++ b/components/autofill/core/common/autofill_pref_names.h
@@ -13,6 +13,7 @@ namespace prefs {
 extern const char kAutofillAuxiliaryProfilesEnabled[];
 extern const char kAutofillEnabled[];
 extern const char kAutofillMacAddressBookQueried[];
+extern const char kAutofillMacAddressBookShowedCount[];
 extern const char kAutofillNegativeUploadRate[];
 extern const char kAutofillPositiveUploadRate[];
 extern const char kAutofillUseMacAddressBook[];